Xinran Ji died from swelling and bleeding inside his brain after being struck on the head at least six times with a blunt object, possibly a baseball bat, testified a L.A. County medical examiner Wednesday as prosecutors revealed evidence about the killing.

The 24-year-old from China was attacked last summer in an attempted robbery near his apartment, blocks from where he studied engineering at the University of Southern California.

Deputy medical examiner Louis Pena said any one of six blows could have been fatal. Ultimately, the brain stem, which controls one’s breathing and heart rate, failed as capillaries ruptured and bled.

Jonathan DelCarmen, 19, and Andrew Garcia, 18, could face capital punishment for murder committed on July 24 in the attempt of robbery. Alejandra Guerrero, 16, and Alberto Ochoa, who recently turned 18, could face life in prison without parole. As minors, they are exempt from the death penalty.

Their families sat alongside Ji’s supporters in court on Wednesday. But Ji’s parents remain in China, frustrated with the American judicial system and its frequent delays. They get updates about the case through their attorney, Rose Tsai, who has refrained from sharing the gruesome details that have emerged in the preliminary hearing.

“They’re not here because they’re very much recovering,” she said. “We don’t want to make them suffer.”

Pena said the injuries he documented hint at the struggle between Ji and the teenagers.

Bruising on Ji’s inner forearm suggests someone might have grabbed him. Discolorations on the back of Ji’s hand and forearm indicated he might have flung his arms across his face in defense.

Dark circles ringing his eyes – described by Pena as “racooning” – resulted from internal bleeding. Ji also had his nose broken, making him swallow blood. The intensity of strikes to the head made Ji’s skull fracture in several places.

Onlookers gasped to see photos of Ji’s bruised and lacerated face. As the prosecutor called up an image of Ji’s skull, cut open for autopsy, Guerrero buried her face in her orange jail uniform. She then turned towards a back wall before fixing her eyes on her lap. Ochoa and DelCarmen stared at the images blankly.

Deputy District Attorney John McKinney, seated next to Det. Paul Shearholdt, examines witnesses to reveal evidence in the death of Xinran Ji. | Daina Beth Solomon

Garcia was the only defendant absent from the courtroom — proceedings against him were suspended Tuesday pending an evaluation next month to determine if he is mentally competent to stand trial. He still managed to become a prominent character in Wednesday’s hearing as a police officer recounted interviews with the defendants.

Their accounts, while conflicting, largely supported the coroner’s findings – as well as security camera footage played in court a day earlier.

According to Los Angeles Police Det. Paul Shearholdt, the group smoked marijuana before driving to USC looking for people to rob – which they called “flocking.”

They targeted Ji because he looked Chinese, said Garcia, who told the detective: “Because he was Chinese, he must have money.”

Ochoa’s plan was to hit Ji to the ground with a metal baseball bat and rummage through his pockets.

“When that didn’t happen he punched him in the face,” Shearholdt said. “The victim responded by running away.”

Defendants gave mismatched accounts of how the remaining blows were dealt as Garcia, Ochoa and Guerrero ran after Ji and knocked him to the ground. But it appears the violence quickly escalated.

According to Garcia, Ochoa jabbed at Ji with the end of the bat. For his part, Ochoa saw Guerrero hit Ji with a wrench, and heard her say she “got his ass.”

In Guerrero’s version, her job was to act as a lookout. She hit Ji’s hand with a wrench several times when he grabbed at her arms, crying and screaming in a language she didn’t understand – and bleeding profusely.

Deputy District Attorney John McKinney said yesterday that Ochoa was the first to turn the baseball bat on Ji. The suspect then passed it to Garcia, who chased Ji around the corner and slammed him again. Guerrero came quickly after, also striking Ji. DelCarmen later drove behind the group, picking up his alleged accomplices in a dark blue 1993 Honda Accord.

Prosecutors expect to finish presenting evidence Thursday, when a judge will decide if the case proceeds to trial.

Tsai, representing Ji’s parents, said they hope for the maximum punishment possible for their son’s death.

“It did not just rob Xinran of his young life,” she said. “But really destroy the family.”

Alejandra Guerrero, in orange, is escorted out of the courtroom during a recess. Bailiffs prepare Alberto Ochoa, also in orange, along with Jonathan DelCarmen, in blue, to follow. | Daina Beth Solomon